Medical Terminology: Components, Word Roots, Prefixes, Suffixes, and Plural Endings

Ch.1 Introduction to Medical Terminology

Medical Term Components

Medical terminology is constructed from specific word parts, each contributing to the overall meaning of the term. Understanding these components is essential for interpreting and forming medical terms.

• Word Root: The core part of the term, providing the fundamental meaning. Example: cardi means heart.

• Combining Vowel: Usually 'o' or 'i', used to connect word roots or a word root and suffix, especially when the suffix begins with a consonant.

• Prefix: Added to the beginning of a term, modifies meaning by indicating direction, position, quantity, time, size, or opposite.

• Suffix: Added to the end of a term, modifies meaning and provides information about condition, disease, procedure, action, or location.

• Eponyms: Terms derived from people's names, not built from word parts.

Example: Electrocardiogram breaks down as follows: Electro- (electricity), cardi/o (heart), -gram (record or image).

Defining Medical Terms

To define a medical term, follow these steps:

• First, define the suffix (condition/disease, procedure, etc.).

• Then, define the prefix (direction, position, quantity, etc.).

• Finally, define the word root (core meaning).

Example: Hypoglycemia = hypo- (under, below), glyc (sugar), -emia (condition of the blood).

Forming Terms from Word Parts

Medical terms are formed by combining word roots, prefixes, suffixes, and combining vowels.

• Use a combining vowel when the suffix starts with a consonant or when joining two word roots.

• Add the suffix to the end of the word root.

• Add the prefix to the beginning of the word root.

• Interpret the meaning by combining all components.

Example: Antipathogenic = anti- (against), path/o (disease), -genic (producing).

Word Roots

Common Combining Forms and Their Meanings

Word roots are the foundation of medical terms. Memorizing common roots helps in understanding and constructing terms.

• append/o: appendix

• carcin/o: cancerous

• cis/o: to cut

• dermat/o: skin

• encephal/o: brain

• enter/o: small intestine

• eti/o: cause (of disease)

• gastr/o: stomach

• gynec/o: woman, female

• hemat/o: blood

• laryng/o: larynx

• macr/o: large

• mamm/o: breast

• nephr/o: kidney

• ophthalm/o: eye

• ot/o: ear

• path/o: disease

• pulm/o: lung

• rhin/o: nose

Example: Etiology is the study of the causes of disease or condition.

Prefixes

Prefixes on Numbers and Amount

Prefixes provide details about numbers, sizes, or amounts in medical terms.

• nulli-: none

• semi-, hemi-: half

• poly-: many

• uni-: one

Example: Polyotia means having more than two ears.

Prefixes That Indicate a Quality

These prefixes modify the meaning of a word to describe a particular attribute or characteristic.

• brady-: slow

• dys-: difficult, bad, painful

• eu-: good, normal

• heter-: different

• mal-: bad, abnormal

• mega-, megal-: very large

• neo-: new

• tachy-: fast

• ultra-: beyond normal

Example: Dyspnea means difficulty breathing.

Prefixes on Position and Placement

These prefixes specify location, direction, or spatial relationship.

• ante-, pre-: in front of

• dorsi-, dorso-: behind

• ep-, epi-: over, above, on top of

• infer-, infra-, hypo-: below, under

• circum-: around

• peri-: surrounding

• ab-: away from

• ad-: toward

• ec-: outside, out

• intra-: within

• inter-: between

• para-: beside, near

• dia-: through

Example: Hypothermia means below normal body temperature.

Suffixes

General Use Suffixes

Suffixes are added to the end of medical terms to indicate condition, action, body component, specialty, or treatment.

• -blast: immature cell

• -cyte: cell

• -logy: study of

• -therapy: treatment

• -thermy: heat

Example: Hepatoblast refers to an immature liver cell.

Grammatical Suffixes: Nouns and Diminutives

Grammatical suffixes convert word roots into nouns, adjectives, or diminutives (indicating something small).

• -icle, -ole, -ula, -ule: diminutive suffixes (e.g., ventricle, pustule)

Pathological Conditions – Standalone Terms

Some suffixes can be medical terms on their own, indicating specific pathological conditions.

• -mania: obsession

• -phobia: fear

• -edema: swelling

• -emesis: vomiting

• -asthenia: weakness

Example: Hematemesis means vomiting blood.

Pathological Conditions – Other Suffixes

• -algia: pain

• -itis: inflammation

• -lepsy: seizure

• -malacia: softening

• -megaly: enlargement

• -oma: tumor

• -pathy: disease

• -penia: deficiency

• -phasia: speech

• -plegia: paralysis

• -rrhage: bursting forth

• -rrhea: flow, discharge

• -rrhexis: rupture

Example: Fibromyalgia is a condition characterized by chronic muscle pain.

Diagnostic & Surgical Procedures

• -tomy: surgical incision

• -ectomy: surgical removal

• -stomy: new opening

• -centesis: surgical puncture to drain fluid

• -desis: binding or joining

• -rrhaphy: suturing

• -graph: recording instrument

• -graphy: recording technique

• -meter: measuring instrument

• -metry: measuring technique

• -scope: examination instrument

• -scopy: examination technique

Example: Otoscope is a device used for visual examination of the inside of the ear.

Plural Endings

Formation of Plural Endings

Many medical terms have singular and plural forms based on Latin or Greek origins. Understanding these endings is important for accurate communication.

• -is becomes -es (e.g., metastasis → metastases)

• -um becomes -a (e.g., flagellum → flagella)

• -ex becomes -ices (e.g., cortex → cortices)

• -us becomes -i (e.g., bronchus → bronchi)

• -nx becomes -nges (e.g., larynx → larynges)

Singular	Plural
metastasis	metastases
flagellum	flagella
cortex	cortices
bronchus	bronchi
larynx	larynges

Example: The plural form of metastasis is metastases.

Summary Table: Medical Term Components

Component	Definition	Example
Word Root	Core meaning	cardi (heart)
Combining Vowel	Connects word parts	o in cardi/o
Prefix	Beginning, modifies meaning	hypo- (below)
Suffix	End, modifies meaning	-emia (blood condition)

Additional info: Academic context and examples were expanded for clarity and completeness. Only images directly relevant to the explanation of word roots were included.